ls command

Hi,

I have come accross what seems to be a bug with the ls command.  It only
happens in directories over a few thousand entries.

For example, the directory I am testing has roughly 7,000 files.  We
tried using:

ls *_* 

This produces a failure, [Too Many Arguments].

These all work fine:
ls
ls -altr
ls -1

I tried other commands like find, tail, and grep. All work fine.
        find . -name "*_*" -exec ls -l {} \;
        tail *_*
        grep "DATA ERROR" *_*

BTW, the *_* produces ~4,300 files out of 7,000.

Not sure if others have seen this type of failure.

Regards,
Rich Jones